Electrospun plasma‐modified chitosan/poly(ethylene terephthalate)/ferrocenyl‐substituted N‐acetyl‐2‐pyrazoline fibers for phosphate anion sensing

Two ferrocenyl‐substituted N‐acetyl‐2‐pyrazolines, N‐acetyl‐3‐(2‐furyl)‐5‐ferrocenyl‐2‐pyrazoline (Fc‐1) and N‐acetyl‐3‐(2‐thienyl)‐5‐ferrocenyl‐2‐pyrazoline (Fc‐2) electrospun fibers, were produced in the presence of plasma‐modified chitosan (PMCh)/poly(ethylene terephthalate) (PET) supporting polymers with an electrospinning method. The morphological and chemical characterizations of the PMCh/PET/Fc‐1 and PMCh/PET/Fc‐2 electrospun fibers were determined by scanning electron microscopy coupled with energy‐dispersive X‐ray spectroscopy analysis. Thermogravimetric analysis results indicated the presence of ferrocene within the PMCh/PET nanofibers. The electrochemical behavior of the PMCh/PET/Fc‐1 and PMCh/PET/Fc‐2 electrospun fibers were investigated by cyclic voltammetry measurements based on the ferrocene/ferrocenium redox couple. The new PMCh/PET/Fc‐1 and PMCh/PET/Fc‐2 electrospun fibers aggregated on the indium tin oxide were used for phosphate anion sensing. The highest oxidation peak currents were observed for the PMCh/PET/Fc‐1 electrospun fibers at about 0.56 V in 0.1M phosphate buffer. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43344.     

Investigation of the relation between meteorological parameters,North Atlantic Oscillation and groundwater levels in Torbali Region,Turkey

Groundwater, the most reliable fresh water source, is used for drinking, domestic and agricultural purposes. Thereby, understanding its behaviour is important for the sustainability of groundwater sources. In this study, relations between the trends of climate parameters [recharge depending on precipitation, temperature and North Atlantic Oscillation Index (NAOI)] and groundwater levels trend were investigated for Torbali Region in Turkey. The human impact that is one of the deterministic components on the groundwater level has been removed from the groundwater level data sets. An increasing trend was observed in the early 1990s, and turning points were determined by using paired t‐test. The trends of the groundwater levels indicate that climate parameters affect groundwater levels in the similar manner. According to the results of the analyses, it is revealed that there is a similar linear variation that is strong and inverse between the trends of NAOI and meteorological indicator (temperature and recharge) and groundwater level.     

Coenzyme Q10 supplementation and diastolic heart functions in hemodialysis patients: A randomized double‐blind placebo‐controlled trial

Coenzyme Q10 (CoQ10) supplementation has been shown to improve diastolic heart function in various patient cohorts. Systolic and diastolic dysfunctions are common in patients with end‐stage renal disease. Favorable effects of CoQ10 on cardiac functions are yet to be seen in hemodialysis patients. We aimed to evaluate effect of CoQ10 supplementation on diastolic function in a cohort of maintenance hemodialysis patients. This was a prospective, double‐blind, placebo‐controlled, crossover study in which all patients received placebo and oral CoQ10 200 mg/d during the 8 weeks in each phase, with a 4‐week washout period. Participants underwent conventional and tissue Doppler echocardiography before and after each study phase. Parameters characterizing left ventricle diastolic function and other standard echocardiographic measurements were recorded. Twenty‐eight patients were randomized, but 22 patients completed study protocol. Intraventricular septum (IVS) thickness and left ventricle mass were significantly decreased in CoQ10 group (P = 0.03 and P = 0.01, respectively). Myocardial peak systolic and early diastolic velocities derived from IVS were significantly increased (P = 0.048 and P = 0.04, respectively). Isovolumetric relaxation time and E/Em ratio calculated for IVS also significantly reduced in CoQ10 group (p = 0.02 and p = 0.04, respectively). There was no significant difference in any of the studied echocardiographic parameters in placebo group. The results of this study showed that CoQ10 supplementation did not significantly improved diastolic heart functions compared with placebo in maintenance hemodialysis patients.     

Characterization of polypyrrole/azocalix[4]arene salts: Electrical properties and thermal stability

Polypyrrole (PPy) was doped with the azocalix[4]arene [(5,11,17,23‐tetrakis[(p‐carboxyphenyl)azo]25,26,27,28‐tetrahydroxycalix[4]arene)] host species. PPy/azocalix[4]arene salts were characterized by FTIR, TGA, SEM, X‐ray diffraction, and conductivity measurements. The properties of PPy were investigated in the presence of azocalix[4]arene host species. The conductivity of PPy increased in the presence of azocalix[4]arene. TGA results indicated that the PPy/azocalix[4]arene salts have higher thermal stability than PPy. It was observed from SEM analysis that the particle diameter of PPy decreased with increasing content of azocalix[4]arene. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Comparative study of conducting polyaniline/copper and polyaniline/nickel composites in the presence of surfactants

Polyaniline/copper and polyaniline/nickel composites were synthesized in the presence and absence of surfactants using ammonium persulfate as an initiator. The structural and surface characteristics of the composites were studied and compared using different techniques. The interfacial interactions and thermal stability of the composites were characterized using X‐ray diffraction and thermogravimetric analysis. Surface properties were investigated using scanning electron microscopy and energy‐dispersed X‐ray spectroscopy. The results indicate significant changes in the morphological and physicochemical properties of the composites when incorporating surfactants. The surfactant‐induced surface characteristics also have an effect on conductivity. Copyright © 2010 Society of Chemical Industry     

PARAMETER ESTIMATION IN CAKE WASHING

The uniform-film model for cake washing considers the cake to be composed of channels in which a stagnant film of solute-rich filtrate adheres to the surface of the channel.

Two independent methods are presented for an unbiased evaluation of the uniform-film model parameters. The first is an iterative procedure which requires adjustment of only one model parameter, and the second is a direct analytical procedure based on the method of moments. Both require experimental data to identify the model parameters.

Application of the two methods give wet-base porosities greater than unity which suggests that the experimental data used to determine the model parameters is beyond the domain of applicability of the uniform-film model.     

Influence of surfactants on properties of electrochemically synthesized pyrrole/1-dimethylaminopyrrole copolymer

The electrochemical copolymerization of pyrrole (Py) and 1-dimethylaminopyrrole (DMAPy) was successfully carried out in the presence of three different types of surfactant (anionic, cationic and non-ionic) by cyclic voltammetric method. The influence of anionic (sodium dodecylbenzenesulfonate) (NaDBS), cationic (tetradecyltrimethylammonium bromide) and non-ionic poly(ethylene oxide)(10) iso-octylphenyl ether (Tween 20) surfactants on the properties of copolymer was investigated. The copolymer has been characterized by the cyclic voltammetry, fourier transform infrared spectroscopy, UV–Vis spectroscopy, scanning electron microscopy, thermogravimetric analysis and conductivity measurements. The results confirmed that the electrochemical reaction of Py and DMAPy in the presence of surfactants generated copolymers. The type of surfactant had an effect on the structural, morphological, thermal and conductivity properties of the copolymers in different ways. According to the initial decomposition temperatures, the thermal stability of the copolymers improved in the presence of surfactants. Py/DMAPy copolymer synthesized in the presence of anionic surfactant NaDBS had the highest initial decomposition temperature (320 °C). The copolymer prepared using various surfactants exhibited different morphologies. The electrical conductivity of pyrrole/1-dimethylaminopyrrole copolymer (8.39 × 10^?3 Scm^?1) was improved using surfactants, especially with anionic surfactant (3.75 × 10^?2 Scm^?1) due to the incorporation of NaDBS into the PPy polymer chain that resulted in a more compact morphology and reduced size of PPy globules.     

Electrochemical Polymerization of Thiophene and Poly(3-hexyl)thiophene,Nanocomposites with TiO2, and Corrosion Protection Behaviors

Thiophene, 3-hexylthiophene, and their nanocomposites with TiO₂ were electropolymerized on Al1050 electrode by chronoamperometric technique. Different concentrations of thiophene and 3-hexylthiophene homopolymers and their nanocomposites with TiO₂ (2% in total content) were characterized by attenuated total reflection Fourier transform infrared spectroscopy, scanning electron microscopy, energy dispersion X-ray analysis, and electrochemical impedance spectroscopy. The anticorrosion tests for homopolymers and nanocomposite films were examined on Al1050 in 3.5% NaCl solution. Poly(3-hexylthiophene)/TiO₂ nanocomposite films gave the highest protection efficiency of 98% because the amount of defects was much lower than that for the poly(3-hexylthiophene), polythiophene, and polythiophene/TiO₂ films.     

The Bleaching of Soybean Fabric by Different Treatments Combined with Ozonation

This article is about bleaching of soybean fibers. Although the studies related to dyeing of soybean fibers have been found in the literature, little has been reported on the effect of bleaching. The natural color of soybean protein fibers is pale yellow or cream, and it is therefore usually necessary to bleach them to improve their whiteness. Different bleaching treatments combined with ozonation were performed in order to establish the effect on whiteness, yellowness, lightness, wettability, hydrophility, moisture sorption, and fiber damage properties of knitted soybean fabric. As a result of study, bleaching process combined with ozonation (ozonation + oxidative bleaching + reductive bleaching) supplied soybean fabric with a white appearance (highest whiteness degree), highest hydrophility, and minimal fiber damage.